1. Field of the Disclosure
This disclosure generally relates to an optical navigation device and, more particularly, to an optical navigation device and failure identification method thereof operating based on the noise map.
2. Description of the Related Art
Images captured by an optical tracking engine generally include a fixed noise pattern, wherein said fixed noise pattern may be caused by photodiodes of the image sensor, optical elements or the light source itself. In order to increase the accuracy of post-processing, the fixed noise pattern may be removed from the current image using algorithm according to a previously constructed noise map.
For example before shipment, it is able to illuminate an image sensor of the optical tracking engine with a uniform light source and record non-uniform positions of an outputted image to be served as a predetermined noise map. In actual operation, fixed noises can be eliminated using algorithm executed by a processor. In other words, conventionally said noise map is used to eliminate fixed noises in the process of image processing.
However, in the optical tracking system requiring high accuracy, in addition to the defects existing in the device itself, the operating environment may also cause the particle contamination of the optical tracking system so as to form the fixed noise. Accordingly, the optical tracking system is preferably able to identify whether failure may occur in the optical tracking engine according to the current image captured in actual operation.